U.S. patent application number 12/311178 was filed with the patent office on 2010-01-07 for power supply device with power factor correction and (startup) current limitation.
This patent application is currently assigned to Recaro Aircraft Seating GmbH & Co., KG. Invention is credited to Wolfgang Wagner.
Application Number | 20100002479 12/311178 |
Document ID | / |
Family ID | 38962878 |
Filed Date | 2010-01-07 |
United States Patent
Application |
20100002479 |
Kind Code |
A1 |
Wagner; Wolfgang |
January 7, 2010 |
Power supply device with power factor correction and (startup)
current limitation
Abstract
A power supply device, particularly for an airplane, has a
control unit that is provided to match a current path to a voltage
curve. An embodiment relates to a rectifier with power factor
correction in the form of a step-up converter with switchable
(startup) current limitation.
Inventors: |
Wagner; Wolfgang;
(Friedrichshafen, DE) |
Correspondence
Address: |
POSZ LAW GROUP, PLC
12040 SOUTH LAKES DRIVE, SUITE 101
RESTON
VA
20191
US
|
Assignee: |
Recaro Aircraft Seating GmbH &
Co., KG
Schwabisg Hall
DE
|
Family ID: |
38962878 |
Appl. No.: |
12/311178 |
Filed: |
August 31, 2007 |
PCT Filed: |
August 31, 2007 |
PCT NO: |
PCT/EP2007/007607 |
371 Date: |
March 20, 2009 |
Current U.S.
Class: |
363/73 |
Current CPC
Class: |
Y02B 70/126 20130101;
H02M 1/4225 20130101; Y02B 70/10 20130101; H02M 3/158 20130101 |
Class at
Publication: |
363/73 |
International
Class: |
H02M 7/00 20060101
H02M007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 22, 2006 |
DE |
102006044879.0 |
Claims
1. A power supply apparatus, particularly for an aircraft, having a
regulatory unit which is provided for the purpose of aligning a
current profile with a voltage profile, the power supply apparatus
comprising: at least one active unit having at least one
connectable unit.
2. The power supply apparatus as claimed in claim 1, wherein the
active unit is provided for the purpose of connecting the unit in a
range of a zero crossing in the voltage profile.
3. The power supply apparatus as claimed in claim 1, wherein the
connectable unit is formed by a resistor unit.
4. The power supply apparatus as claimed in claim 3, wherein the
unit has at least one ohmic resistor.
5. The power supply apparatus as claimed in claim 1, wherein the
unit has, at least in one range, at least one parameter which is
dependent on a temperature value in order to achieve a specific
temperature response.
6. The power supply apparatus as claimed in claim 5, wherein the
unit has an NTC response.
7. The power supply apparatus as claimed in claim 1, wherein the
active unit has at least one control unit which is provided for the
purpose of initiating a switching operation at least at a
particular phase angle.
8. The power supply apparatus as claimed in claim 1, wherein the
active unit comprises at least one comparator.
9. A method for aligning a current profile with a voltage profile
using a regulatory unit, particularly for application in an
aircraft, wherein a unit is connected in the range of a zero
crossing.
10. The method as claimed in claim 9, wherein a resistor unit is
connected.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a U.S. national stage application of
PCT/EP2007/007607 filed on Aug. 31, 2007, and claims priority to,
and incorporates by reference, German Patent Application No. 10
2006 044 879.0 filed on Sep. 22, 2006.
BACKGROUND
[0002] The invention is based on a power supply apparatus.
[0003] Power supply apparatuses, particularly for application in
aircraft, are already known which have a regulatory unit and which
are provided for the purpose of aligning a current profile with a
voltage profile.
SUMMARY
[0004] The invention is based on a power supply apparatus,
particularly for an aircraft, having a regulatory unit which is
provided for the purpose of aligning a current profile with a
voltage profile. In this context, "aligning" is to be understood to
mean particularly at least approximating the voltage profile to the
current profile.
[0005] It is proposed that the power supply unit have at least one
active unit having at least one connectable unit. In this context,
an "active unit" is to be understood to mean particularly a unit
which is provided for the purpose of at least semi-automatically
implementing a switching operation. In addition, the "connectable
unit" is intended to be understood to mean particularly a unit
which can be used to influence the current profile in an operating
range. Undesirable differences between the current profile and the
voltage profile despite the regulation by the regulatory unit can
therefore advantageously be at least counteracted. Furthermore, it
is possible to achieve filtering in a further frequency range,
particularly between 350-800 Hz, a distortion factor can be
improved and it is possible to attain advantageous limiting for an
inrush current.
[0006] If the active unit is provided for the purpose of connecting
the unit in the range of a zero crossing in the voltage profile, it
is possible to at least reduce difference errors particularly in
the range of the zero point in the voltage profile or at the zero
crossing. In this case, "range of a zero crossing in the voltage
profile" is intended to be understood to mean particularly a range
below 30%, preferably below 20% and particularly advantageously
below 15% of the maximum applied voltage.
[0007] The unit may be formed by various units which appear
appropriate to a person skilled in the art, particularly
advantageously by a unit which has an at least essentially linear
response in at least one operating range, preferably at a zero
crossing of the voltage, "essentially" being intended to be
understood to mean particularly that the response thereof differs
from a theoretically fully linear response by less than 10%.
[0008] In addition, the unit is particularly advantageously formed
by a resistor unit, a "resistor unit" being intended to be
understood to mean particularly a unit which is provided for the
purpose of simulating an ohmic resistor at a zero crossing in at
least one operating range, such as a field-effect transistor,
and/or preferably has at least one ohmic resistor, which means that
the resistor unit is simple to implement particularly in design
terms. A resistor unit can advantageously easily be used to achieve
the filtering in a further frequency range, to improve the
distortion factor, and it is possible to attain advantageous
limiting of an inrush current, specifically particularly by virtue
of it being possible to dispense with an input resistor for the
regulatory unit or to at least reduce the resistance value of said
input resistor.
[0009] If the unit has, at least in one range, at least one
parameter which is dependent on a temperature value in order to
achieve a specific temperature response, it is advantageously
possible to achieve desired automatic adjustment to a varying
temperature value, and advantageous linearization over the load can
be attained. "Specific temperature response" is in this case
intended to be understood to mean particularly that the unit is
chosen specifically such that its response changes with the
temperature value.
[0010] Particularly advantageously, the unit has an NTC (Negative
Temperature Coefficient) response, so that as the temperature rises
a parameter falls, such as advantageously an electrical resistance,
which means that increased safety can be achieved. To attain the
NTC response, the unit may have various components which appear
suitable to a person skilled in the art, but the unit
advantageously has at least one NTC resistor, which allows an
appropriate response to be implemented easily and inexpensively in
design terms.
[0011] In a further refinement of the invention, it is proposed
that the active unit have at least one control unit which is
provided for the purpose of initiating a switching operation at
least at a particular phase angle, which means that interference
effects occurring at particular phase angles can be counteracted
specifically. In this case, the control unit may be formed by
various units which appear appropriate to a person skilled in the
art, such as particularly by phase angle comparators and/or by
units which switch at particular times, for which there are
particular phase angles, etc. A switching threshold may be coupled
to a phase and/or to an amplitude.
[0012] Preferably, the active unit has at least one comparator,
which means that a desired switching operation, particularly at a
particular phase angle, can be achieved specifically, in a manner
which is simple in design terms.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Further advantages can be found in the description of the
drawing which follows. The drawing shows an exemplary embodiment of
the invention. The drawing, the description and the claims contain
numerous features in combination. A person skilled in the art will
expediently also consider the features individually and combine
them to form appropriate further combinations.
[0014] In the drawing,
[0015] FIG. 1 shows a schematic illustration of a power supply
apparatus according to the invention, and
[0016] FIG. 2 shows a voltage profile.
DETAILED DESCRIPTION
[0017] FIG. 1 shows a schematically illustrated power supply
apparatus for an aircraft having a regulatory unit 10 which is
provided for the purpose of aligning a current profile with a
voltage profile 12 (FIGS. 1 and 2). The regulatory unit 10 is
connected to an AC (Alternating Current) current source--not shown
in more detail--by means of the connections 24, 26 and, following
the connection, has an NTC resistor 28 in order to limit an inrush
current. The NTC resistor 28 is followed by a bridge rectifier 30
in the regulatory unit 10. In addition, the regulatory unit 10
comprises a buffer capacitor 32 for a switch 34 in the regulatory
unit 10, said switch being switched by a PFC (Power Factor
Correction) chip 36 in the regulatory unit 10. In addition, the
regulatory unit 10 has an electronic unit 38 which is coupled to
the PFC chip 36 and has an inductor and an auxiliary coil for
storing energy, a diode 40 for rectification which is connected
downstream of the electronic unit 38, and a capacitor 42 which is
connected downstream of the diode 40. In addition, the regulatory
unit 10 has resistors 44, 46 for voltage feedback which are
connected downstream of the diode 40 and in parallel with the
capacitor 42, with a path 48 coupled between the resistors 44, 46
being routed to the PFC chip 36. The task of the regulatory unit 10
is to produce a current which follows the sinusoidal shape of the
voltage as exactly as possible. This applies both to the sinusoidal
shape of the current and to the phase between current and voltage.
This means that the regulatory unit 10 is provided for the purpose
of more or less simulating a resistive load.
[0018] Besides the regulatory unit 10, the power supply apparatus
has an active unit 14 having a connectable unit 16 which is formed
by an ohmic NCT resistor. The active unit 14 is connected
downstream of the switch 34 in series at the docking points
identified by A and B or is integrated into the current path of the
switch 34. Referring to FIGS. 1 and 2, the active unit 14 has a
control unit 22 which is formed by a comparator and which is
provided for the purpose of comparing a voltage applied downstream
of the bridge rectifier 30 with a reference voltage U.sub.ref which
is between 5% and 15%, preferably approximately 10%, of the maximum
voltage or approximately 15 V, and hence connecting the unit 16 in
a range 18 of a zero crossing 20 in the voltage profile 12 by means
of a switch 50 at a particular phase angle. Starting from a
connection 52 downstream of the bridge rectifier 30, a path 54 to
the control unit 22 has a resistor 56 connected upstream of it and
a resistor 58 connected downstream of it, the second resistor 58
being grounded.
[0019] Above the reference voltage U.sub.ref, the switch 50 is
closed. Once the reference voltage U.sub.ref is undershot, the
control unit 22 opens the switch 50 and the current from the switch
34, which is controlled by the PFC chip 36, flows via the unit 16,
and this affects the clock frequency of the PFC chip 36 by virtue
of a soft characteristic curve being achieved and the clock
frequency being lowered as a result. In addition, the connection
affects the sinusoidal current of the asynchronous generator by
virtue of an actual ohmic resistor being present. When the
sinusoidal input voltage rises above the reference voltage
U.sub.ref again, the unit 16 is shorted by the switch 50 again and
is therefore inoperative.
[0020] When the AC current source is switched on or when the system
is started up, the switch 50 is open. The current accordingly flows
through the unit 16 formed by the NTC resistor and is limited to a
known value. After a certain time when the system has been
initiated, the switch 50 closes and the unit 16 formed by the NTC
resistor is shorted. At this time, the capacitor 42 holds a charge
and, without the active unit 14 and without the NTC resistor 28,
would have resulted in a high inrush current, so that the
deactivation of the unit 16 formed by the NTC resistor has no
consequences. As a result of the active unit 14, the NTC resistor
28 can advantageously be provided with small dimensions or even
eliminated completely, which means that losses and resultant
heating can at least be reduced.
[0021] The design of the unit 16 as an NTC resistor means that
malfunctions and overheating can be avoided in the event of the
switch 50 failing.
* * * * *